Original scientific paper

Stereochemical Studies of some 12a-Substituted Rotenoid Derivatives

Ivanka Kostova ; Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Nikolina Berova ; Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Petko Ivanov ; Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Bozhana Mikhova ; Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Rositza Rakovska ; Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Gunther Snatzke ; Lehrstuhl fur Strukturchemie, Ruhruniversitat, Postfach 10 21 48, D-4630 Bochum, Germany

Abstract

The absolute configuration at 6a and 12a positions as well as the conformation of rings B and C of some cis fused 12a-substituted (OH, CH2OH, CH2OCOR’) synthetic derivatives of natural rotenoids, rotenone and amor- phigenin, are discussed on the basis of 'H NMR, CD and molecular mechanics studies.
The CD Cotton effects above 300 nm of all 12a-substituted derivatives, compared with those of the parent natural rotenoids, show an unexpected sign inversion and cannot be used for reliable configurational assignment. This has been achieved in a nonempirical way by application of the exdton chirality method.

Keywords

Hrčak ID:

137272

URI

https://hrcak.srce.hr/137272

Publication date:

29.2.1992.

Visits: 1.027 *